What Happens If The Batteries Get Wet?

[Joe Mullee]

My house and starter batteries are located in those plastic battery boxes and secured to the sole inside the cabin. The boxes have small vents to allow for the escape of gasses. I was wondering what would happen if the batteries ever got wet. They are all in the same vicinity as the water heater and galley sink.

Just wondering.

Joe Mullee

 

[Stu Jackson]

How wet is wet (not what "is" is). Underwater, hardly good. A light spray, just clean it up.

More importantly, why do you ask? Any strange plans we should know about? How could they if they're in the boxes?

 

[Joe Mullee]

They're In Boxes

Stu,

I just put a new water heater in because the old one wasn't working anymore. My batteries are located right next to the heater and I had to move them around a little while I was doing the work. They are in boxes but due to their proximity to the water heater it got me wondering "what if". Everything is good and I have no plans to take them out of the boxes. Thanks for your response.

Je Mullee

 

[Benny]

I was operating a 17' bowrider once and we were swamped by two rogue waves in succession. The boat's built in bouyancy kept it afloat while the trusty outboard continued to operate. I turned on the bilge pump and we started bailing. It took about 15 minutes to bail the water out and when I placed my hands in the gearlever I received an electric shock but decide to power up and get back. The engine and boat ran flawlesly for about an hour to get to the ramp. After we pulled the boat out of the water we checked the batteries and both boxes were totally full with water sloshing between the terminals. The batteries suffered no damage even though there was electricity traveling all over the boat. Perhaps it was due to the fact the engine was running and the alternator was putting out amps. They did not loose any charge and seemingly no salt water got in the cells. From my experience I would say some water splash should not harm a battery.

 

[Brian M H23]

12V dc and water is surprisingly not conductive! Imagine the difference between shorting your battery terminals with a 500 ohm resistor and a piece of 10 guage wire. Total submersion is another thing, obviously

As a side note, I drilled a small drain hole in my battery box about 4" up. That way, if something does happen and water gets in the box, it doesnt sit in the box and short my battery, it drains into the bilge.

 

[Stu Jackson]

As long as your water heater's pressure relief valve is facing the other way it shouldn't be an issue. If so, just add small drain hose to the valve. I haven't heard of one of those popping, ever. BTW, only turn your heater on for 20-30 minutes; it'll warm up the water and the six gallons will last a long time; don't leave it on for an extended period of time.

 

[Roger Long]

Any strange plans we should know about?

No firm plans in my case but I am gradually working on increasing Strider's probability of surviving a roll over.

Nice battery boxes on the E 32. They are glassed into the structure as firmly as the bulkheads. The only drawback is their being impossible to replace without major glass work (the engine would probably have to come out). That's why they look a bit funky. I've had to splice the corners back together with galvanized framing angles on the inside. The wooden boxes are lined with plastic battery boxes dropped in.

 

[Ross]

In the old diesel-electric submarines with their high voltage battery banks flooding with seawater created a chlorine gas hazard but I doubt that 12 volts is sufficient to make trouble. Farm tractors are often hosed clean with the batteries in place and then just allowed to dry naturally.

 

[Ron20324]

As a side note, I drilled a small drain hole in my battery box about 4" up. That way, if something does happen and water gets in the box, it doesnt sit in the box and short my battery, it drains into the bilge.[/quote]

As a second side note, when hurricane Isabella blew through Annapolis, the dock boxes were 6 inches underwater. Nice to know the boxes had been good at keeping water OUT, but once filled, they kept water IN. We went around the marina with a cordless drill to make a couple drain holes in each box. ALL, be prewarned!

 

[Stu Jackson]

As a side note, I drilled a small drain hole in my battery box about 4" up. That way, if something does happen and water gets in the box, it doesnt sit in the box and short my battery, it drains into the bilge.

Ron, Uhm, that sounds very dangerous to me. It's OK for dock boxes (although I wouldn't do that to someone else's box), but if the batteries leak acid, and the boxes are there to contain that acid, why would you want that acid spilling into the inside of your boat? If you calculate how much acid's in the battery, then the hole may need to be a bit higher to deal with just water. And if there's a top to the box, how would water get in? Just curious.

 

[Ron20324]

Ron, Uhm, that sounds very dangerous to me. It's OK for dock boxes (although I wouldn't do that to someone else's box), but if the batteries leak acid, and the boxes are there to contain that acid, why would you want that acid spilling into the inside of your boat? If you calculate how much acid's in the battery, then the hole may need to be a bit higher to deal with just water. And if there's a top to the box, how would water get in? Just curious.

Stu, that first side note was a quote from Brian's post. Mine was only in regards to the dock box.

 

[Stu Jackson]

Ah, OK, same answer though, however it applies. Any comments?

 

[sailingdog]

IT depends... if the batteries are wet-cell and submersed in salt water...bad things happen, like the venting of toxic gases... If the batteries get immersed in freshwater, the battery electrolyte dilutes, and you get acid everywhere... milder than if you tipped the batteries, but still a mess...and you need to replace the batteries more likely than not.

If they just get splashed... dry them off.